You’ve heard of Wi-Fi, now you need to hear about Li-Fi. Still in the nascent stage, this new technology could change how you use the Internet. It’s much faster than existing Wi-Fi tech, it’s more energy-efficient, and potentially more secure as well.

But of course, there are just as many downsides.

Li-Fi, or Light Fidelity, is suddenly in the news these days because an Estonian company called Velmenni conducted a real-world test where it was able to transfer data between devices at 1 Gbps, which is roughly 100 times faster than Wi-Fi in the real world. In lab tests, the fastest recorded speed was 224 Gbps!

And it all works with the simple power of light.

What Is Li-Fi?

Li-Fi’s biggest proponent is Harold Haas, a professor at The University of Edinburgh, and founder of the company pureLiFi, which is trying to bring the technology into real world markets.

This means that Li-Fi is completely wireless, much like existing Wi-Fi. Haas also stresses that it can operate with existing LED bulb technology. Note: “existing technology” doesn’t mean “existing LED bulbs” that you already have set up in your house. Li-Fi actually works on wireless protocols much like Wi-Fi’s 802.11.

In short, you’ll need new bulbs. Li-Fi will also require a new piece of technology in your smartphones and laptops: a photosensor. Photosensors (also called photodetectors) are sensors which can “read” incoming light.

That code is then transmitted over infrared light waves by your remote’s sensor, and the light waves are received by your TV’s infrared sensor, which decodes the light and performs the intended input action.

PureLiFi’s infographic above shows how this works. The Internet and router/server is hooked to a cable, and the cable is attached to any number of LED bulbs in your house. The LED bulbs then transmit the data as modulating light waves while a photodetector on your phone or laptop picks up those light waves and decodes them.

So anywhere that your LED bulb is casting light that your photodetector can “see”, you’re ready to get Internet access — and at speeds faster than Wi-Fi.

The Problems With Li-Fi

While all of this sounds really good, there are some major problems that Li-Fi still has to overcome:

Li-Fi cannot be used in direct sunlight (or other odd conditions with harsh lighting) since the photodetectors won’t be able to detect the modulating light waves. It’s unclear what counts as a poor condition, but as Velmenni’s and Haas’s demos have shown, it does work with some amount of ambient lighting.

The line-of-sight requirement can be a major bottleneck. Let’s say you have one Li-Fi bulb in your living room and you want to move to your bedroom. Well, you better have another Li-Fi bulb set up there or you’ll be out of luck.

Li-Fi is going to need reinvestment in lighting and wiring infrastructure.

Will Li-Fi Revolutionize the Internet?

Right now, it’s honestly too early to tell. Advocates of the technology suggest that instead of Li-Fi replacing your existing setup, it’ll be an additional connectivity source that boosts your usage. PureLiFi illustrates this by showing how you are likely to go from LTE to Wi-Fi to Li-Fi in your home:

We probably won’t see a mass rollout of Li-Fi anytime soon. PureLiFi is the leader in this regard and has so far joined up with one French company to hopefully go to market by the third quarter of 2016.

What Does All of This Mean?

The bottom line for you right now? Nothing changes.

Li-Fi seems like really cool technology and could help augment existing Wi-Fi and other wireless connectivity — it could potentially even replace it altogether — but actual usage for us consumers is a long, long time away.

Until that happens, check out Haas’s most recent demonstration of Li-Fi and be amazed by what the marriage of LED bulbs, Li-Fi, and solar cells could bring to our smart homes of the future:

What Do You Think About Li-Fi?

What’s your take on this new wireless tech, is it the future or just a fad? Would you buy into Li-Fi technology any time soon?

I disagree. The true "negative side" has not been raised. The LiFi technology is only showing one direction (download) communication. What about uploading? Before the LiFi system can deliver the desired material, your request for that material still needs to go out. Also, a LiFi connection will not speed up your ISP. You will not get a LiFi promised 1Gbps download if your ISP connection only delivers 50mbps to your location.

U don't make it when it comes into use company's like BT will sell stuff like fittings, bulbs and new hubs that allow u to use lifi and wifi it will come with a free installation or a manual.
The article says that our phones and tablets will have to have built in recivers but that will not be necessary when on the go as in one of LiFi's videos they showed how you could plug in a reciver.

Perhaps devices, particularly mobile devices, could transmit their signal via the screen itself. That might address the issue of power consumption, since the idea is to use a source of light already being utilized. Though, I must admit, there are still serious limitations in my mind that it would not address: How does it work when the screen does not immediately face the receiver, and how you would distinguish that signal from other sources of light or how is it possible to clearly transmit a signal in a dynamic environment with many other user devices transmitting their own photoelectric signals?

So we're going to be eventually see internet in terms of Gigabytes per second, rather than the Megabytes per second we do now? How very... predictable. I remember thinking of internet in terms of Kilobytes per second; in fact, I still do when on a particularly slow connection. Heck, my parents probably remember the days of thinking of connections in terms of Bytes per second.
Everything, and nothing, speeds up as technology advances. Websites will simply continue to increase the amount of data required to load them. My mother remembers the days when one could reliably stream a YouTube video on Dial Up!

Receiving light from the bulb is all well and good, but how do I send data back upstream? Do I now need to attach a light to my computer? And a receiver to my household lamp?
Doesn't sound like a particularly useful technology...

I believe I had read that you would need a special receiver (USB connected) that would also act as a transmitter, at least for desktop computers. As for a smartphone, I suppose it would be the same idea, plug an additional attachment, but unfortunately most probably would also shorten the battery life. The problem I see with this is as with other techologies is the speed you get from your ISP. Sure, on your LAN you could have a Gazillion Bytes Per Second, but if you only have a connection with your ISP at 2-3Mbps, that Gazillion bps won't be of much help. Still, the faster even though locally the better. Maybe in a more mature form, this could be a great technology, but we'll have to wait to see how it evolves.

I have the same concern as you Paul, communication between devices is a two way street which means a device must be capable of receiving information and transmitting it as well. So my guess is that in order for a phone to transmit data it must have a led bulb on every time we want to use this technology and that I believe would be annoying for most of all.

The obvious answer is to use LiFi as a redundant connection asset. We do this Bluetooth and NFC so why not here, at least until it finds its niche or is proven a flawed concept. I, for one, would gladly give it a try.

So it's basically useless if my phone is in my pocket. Right now wi-fi penetrates my jeans pocket and sends data to my phone; whereas for this to be useful I'd have to have my phone sit out on my desk all the time.

I can see the appeal of a dedicated point-to-point data connection for stationary devices such as TV's, access points, hubs, or other connected devices that remain stationary; however, this becomes useless when you have mobile devices that do not always face the same direction with a photosensor always pointing at a bulb. For high-bandwidth devices like a smart tv streaming data, this can be great, but for phones, not so much.

WHy people forget that if LI-FI has to work, u need to conatantly Switch ON your bulbs, IT MEANS MORE ELECTRICITY & ENERGY to be used.
HEre v r tlking abt conserving energy/electricity & to use net u hv to once again waste/use electricity ?
Re-think this plssss..........

I hope it works more efficiently than Infra Red did. I had an IR channel changer in the 70's. Yes, it could change the TV channels at a press of a button, but if I rattled my car keys when I came in the room it also change the channels!! Much to my children's annoyance!

You might be confusing IR technology with Ultrasound. IR remotes could never be confused with rattling keys. Ultrasound remotes had aluminum slugs inside that emitted an Ultrasound each time the were struck by a button. All the human would hear was a click, each time the button was pressed thereby generating the term "clicker" for a TV remote. :)

In Order to over come the light swithing on and off problem.
Can't We Fix The sensor which predict the light and comapre with darkness and once the sensor threshold reaches above the darkness level we can able to fix the system in order to swith the light in black colour which won't effect the Humans.

Just as a point of fact, currently your lights DO flick on an off, ALL AC lights do. They flick on an off at a rate of 120 cycles per second (CPS or Hz) here in the USA. We use 60 Hz as our electrical standard, we get 120 Hz because each cycle is made of of two zero crossing points, thus any light that is driven by household current WILL flicker at 120hz. Ever notice how annoying those LED Christmas lights are? Since they are "solid state" lighting they have nothing to keep glowing during the zero crossing point. With incandescent lamps the filament is still hot and continues to glow during the zero crossing point, even florescent lamps continue to glow during this point due to the phosphors in the tube, that is why we don't notice the flicker. This is called persistence. If the frequency was high enough you never would see the flicker

This demos how the data is transferred from the light to the phone. How does your phone respond? When you click a link for example the phone has to transmit the request back. Does this mean that this would be one way and some thing else used to send the request.

That's exactly what I was wondering??? This would only be downstream. What about upstream? Do you always have to have the lights on to have this work, or will the data wavelengths continue even though you turn off the visible light?

Hello, all.
Light can be harmful; Ever get sunburned, or have your eyes 'flashed' by a welder?
How about the effects of flashing lights?
We already have far too much EMF radiation, w/ the known & unknown effects.
What 'side effects' will this tech have?
It sounds good,
but I have to agree w/ Mr. Borsos; It looks like overkill, and in the wrong medium, too.
Line-of-sight can be very limiting, until more is known about "LiFi,"
not much chance we'll see it soon.
Have a GREAT day, Neighbors!

Hello,
I'm not too sure if you know about led lights.
Have you ever seen the little lights on Christmas trees?
Yeah i don't think of any scenario where an led light can blind someone as much as getting a sunburn, or the flashes of a welder. And even if you're eyes are that sensitive to light, you can apply a filter on it as well. The radiation emiting from the bulb is the exact same as the regular radio waves of youre average wifi. Harmless. If you're going to go on about radiation, and you live anywhere near a city, the city will do you more harm than a little led light.

What if someone has a window in their Li-Fi active room, simply by training a detector from outside on that window you'll be able to pick up the data. It's true it is probably encrypted, but encryption can be broken...So all you'll need now to pick up the data from far away is a decent telescope and a free encryption hacking program.

Communication speeds that exceed SATA 3 are not useful in a home environment. A slower version would be useful for replacing USB with a wireless solution on mobile devices, but I can't imagine using it like a router for 2 way communication. That would mean a "blinking" bright omnidirectional lightsource on my laptop.